The latest crackdown on human rights lawyers working on the mainland that began in July is the most sweeping suppression of dissent since President Xi Jinping came to power in 2012. One of the most egregious cases, however, dates back to the arrest in May last year of Pu Zhiqiang , who has been a vocal critic of anomalies in the mainland's judiciary system. Pu remains in custody after being initially detained by police for "picking quarrels and provoking trouble" following an event marking the Tiananmen Square crackdown.

Four months ago, Beijing prosecutors finally charged him with inciting ethnic hatred as well, while dropping two additional accusations by police - of inciting separatism and illegally obtaining personal information. If the case against Pu is strong the authorities have had ample time to prepare it. But now his trial has been put off for another three months. What sets his case apart is that despite the unexplained trial delays, he is being treated as if he's a convicted criminal. He remains in detention because his lawyers have failed for the second time in an application for his release on bail pending the delayed proceedings. After he had been held for so long, surely it was time to grant bail or at least outline evidence that was strong enough to justify denying it.

The July crackdown resulted in nearly 300 rights lawyers, activists and their families being detained, arrested or barred from leaving the country, according to a rights lawyers' group. Twenty-one have been held on criminal charges or put under "residential surveillance", and seven are missing.